convert weight to mass and vice versa?

We know, 1lb=1 pound=0.4535924kg.

So 2lbs=(2*0.4535924)kg=0.9071848kg.

It's the answer I think.

Hope it helped...

OK, it's clear you need some physics lessons.

First, the mass of something is not measured by pounds. So that "mass of an object is [NOT] 2 lbs...." The mass unit for Imperial units (slug, ft, seconds) is the slug.

Second, mass is an intrinsic physical property. In classical physics that means it's invariant; it does not change. So the mass of an object on the Moon is the same mass it'd have on Earth.

Finally, weight is another name for the force of gravity F = W = mg; where m is the mass (slugs) and g is the gravity field strength (lbs/slug).

Learn the above and then work the problem

If the weight W = 2 lbs = mg; the mass m = W/g = 2/g slugs. You need to memorize g, the gravity field strength in Imperial units. Near Earth's surface g = 32.2 lbs/slug. Solve for m. You can do the math.

Now assuming m = 2 slugs (not lbs), we have W = mg = 2*32.2 = ? lbs. You can do the math.

If you are dealing with pounds force, you best learn the Imperial units.

Avoirdupois pounds are a measure of weight, which is a kind of force. To obtain the mass, you must divide by the acceleration of gravity, which is 32 feet/sec². The resulting figure will be in slugs, not pounds.

The metric system, being more modern, measures mass, not weight. Weight is deemed to be an archaic concept, and not really used in the metric system, and is instead referred to as the force due to gravity acting upon a given mass in kilos or whatever. No one ever calculates "weight" in the metric system, or at least they never call it that.

Hello Orty, you use lb as unit for mass. Let me use in SI units as kg for mass

Now kilo gram is the unit for mass

But weight has unit kg wt. One kg wt ie kilo gram weight equals to g newtons

Here g is the acceleration due to gravity

Note that mass and weight are different physical quantities. Weight = Mass X acceleration due to gravity

So W = M g

W has to be measured in newton and M is to be in kilo gram. g has unit m/s^2

If mass is 30 kg then its weight will be 30 x 9.8 newton Or 30 kg wt